<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        body{
            /*perspective: 500px;*/
        }
        ul{
            margin: 100px ;
        }
        li {
            width: 120px;
            height: 35px;
            list-style: none;
        }
        .box{
            width: 100%;
            height: 100%;
            position: relative;
            transform-style: preserve-3d;
            transition: all 1s;
        }
        .box:hover{
            transform: rotateX(90deg);
        }
        .front,
        .bottom{
            width: 100%;
            height: 100%;
            position: absolute;
            left: 0;
            top: 0;
            text-align: center;
            line-height: 35px;
        }
        .front{
            background-color: pink;
            transform: translateZ(17.5px);
        }
        .bottom{
            background-color: deepskyblue;
            transform: translateY(50%)  rotateX(-90deg);
        }

    </style>
</head>
<body>
<ul>
    <li>
        <div class="box">
            <div class="front">正面</div>
            <div class="bottom">底面</div>
        </div>
    </li>
</ul>
</body>
</html>